Electronic apparatus

ABSTRACT

An electronic apparatus that includes: a housing having two surfaces extending in parallel, and a side surface connecting edges of the two surfaces; a circuit board placed in the housing and extends in parallel with the two surfaces; a plate member that extends to face a first surface of the circuit board; and a fan provided on a second surface of the circuit board, wherein the circuit board has a heat-generating electronic component mounted on the first surface and an opening through which air flows to the second surface side, and the plate member includes a concave groove formed in the first surface; a convex line formed on the second surface facing the circuit board on a portion corresponding to a back surface of the concave groove; and a guiding inclined surface formed on the back of the convex line to guide air to the opening.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority of theprior Japanese Patent Application No. 2008-169646, filed on Jun. 27,2008, the entire contents of which are incorporated herein by reference.

FIELD

The embodiment discussed herein is related to an electronic apparatushaving a built-in circuit board on which a heat-generating electroniccomponent is mounted.

BACKGROUND

A notebook personal computer (hereinafter abbreviated as “note PC”)includes a main unit having a keyboard on its upper surface andheat-generating electronic components such as a CPU inside. The mainunit is devised in various ways to radiate heat, including providingtherein a fan to radiate heat from the heat-generating electroniccomponents.

When a structure, which includes a fan on a second surface of a circuitboard having a heat-generating electronic component mounted on a firstsurface, needs to be employed in consideration of componentarrangements, a problem arises how heat from the heat-generatingelectronic component is efficiently radiated.

Herein, Japanese Laid-open Patent Publication No. 2001-142574 disclosesa structure in which a radiation plate is provided on a back surface ofa keyboard and the radiation plate is brought into contact with aheat-generating electronic component. In the above-describedpublication, a fan is further provided to exhaust air in the inside tooutside. However, the fan exhausts air which flows along a secondsurface of the circuit board to the outside. The second surface is abackside of a first surface on which a heat-generating electroniccomponent is mounted. Therefore, there is a problem that radiationefficiency is poor even though the fan is provided.

Moreover, Japanese Laid-open Patent Publication No. 11-307969 disclosesa structure in which heat-generating electronic components are mountedon a chassis for heat radiation in place of being mounted on a circuitboard. However, when the heat-generating electronic components areprovided separately from the circuit board, wiring is very troublesomeand assembly becomes very complicated.

Further, Japanese Laid-open Patent Publication No. 2008-28193 disclosesa structure in which a hole is formed in a circuit board and air, whichis heated by a heat-generating electronic component mounted on a firstsurface of the circuit board, is passed through the hole, and is guidedto a second surface side to be exhausted by a fan. According to thisstructure, the air heated on the first surface side can be guided to thesecond surface side and efficiency of heat radiation by the fan can beimproved to some degree. However, a problem arises how the air is madeto smoothly flow in the hole.

Furthermore, Japanese Laid-open Patent Publication No. 2003-283159discloses a structure in which a cable is wired by using a groove formedin a chassis, but this has no relation to heat radiation ofheat-generating electronic components.

SUMMARY

According to an aspect of the invention, an electronic apparatusincludes:

a housing that includes two surfaces extending in parallel with eachother, and a side surface connecting peripheral edges of the twosurfaces to each other;

a circuit board that is placed in the housing and extends in parallelwith the two surfaces;

a plate member that extends to face a first surface of the circuitboard; and

a fan that is provided on a second surface of the circuit board, wherein

the circuit board has a heat-generating electronic component mounted onthe first surface and an opening through which air on the first surfaceside flows to the second surface side, and

the plate member includes: a concave groove formed in the first surfacefacing a side opposed to the circuit board; a convex line formed on thesecond surface facing the circuit board on a portion corresponding to aback surface of the concave groove; and a guiding inclined surfaceformed on the back of the convex line to guide air on the first surfaceside of the circuit board to the opening.

The object and advantages of the invention will be realized and attainedby means of the elements and combinations particularly pointed out inthe claims.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and arenot restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view illustrating an appearance of a note PC inan opened state as one embodiment of an electronic apparatus;

FIG. 2 is a perspective view illustrating an appearance of the same notePC as in FIG. 1 in a first closed state;

FIG. 3 is a view illustrating an appearance of the same note PC as inFIGS. 1 and 2 in a second closed state;

FIG. 4 is a view illustrating a bottom surface of the same note PC as inFIGS. 1 to 3;

FIG. 5 is an external perspective view illustrating the same note PC asin FIGS. 1 to 4 and a state in which an antenna unit is provided in astanding manner in the opened state;

FIG. 6 is an external perspective view illustrating the same note PC asin FIGS. 1 to 4 and a state in which the antenna unit is provided in ahorizontally extending manner in the opened state;

FIG. 7 is a front view illustrating a housed state of the antenna unit;

FIG. 8 is a perspective view illustrating a top end portion of theantenna unit and a locking mechanism which locks the antenna unit, afterdetaching a frame body covering the surrounding of a display screen infront of a display unit;

FIG. 9 is a plan view illustrating a portion of the antenna unit and thelocking mechanism after detaching a circuit board that covers thelocking mechanism;

FIG. 10 is a view illustrating the locking mechanism with the slidelever slid;

FIG. 11 is an exploded view of the antenna unit;

FIG. 12 is a perspective view illustrating the center portion ofrotation of the assembled antenna unit seen from an upper cover side;

FIG. 13 is a view illustrating a rotary shaft portion of the antennaunit of an antenna housing section;

FIG. 14 is a view illustrating a plate member;

FIG. 15 is a view illustrating a state in which the plate memberillustrated in FIG. 14 is fitted into a boss illustrated in FIG. 13;

FIG. 16 is a perspective view illustrating a side surface of the samenote PC as those having been described so far in the first closed state;

FIG. 17 is a perspective view illustrating a rear side of the same notePC as those having been described so far in the second closed state;

FIG. 18 is a perspective view illustrating aback surface of the note PCin the opened state;

FIG. 19 is a view illustrating the note PC in the opened state after theupper cover forming a housing of a main unit is detached, together withthe detached upper cover;

FIG. 20 is a view illustrating only the upper cover seen from an angleat which a side surface of the upper cover can be seen;

FIG. 21 is a view illustrating an inner side of a portion, where anoperation member is placed, of the upper cover after putting the uppercover upside down;

FIG. 22 is a view illustrating only the operation member detached fromthe upper cover;

FIG. 23 is a view illustrating a state in which the operation member ismounted on the upper cover (before operation);

FIG. 24 is a view illustrating a state in which the operation member ismounted on the upper cover (after operation):

FIG. 25 is a view illustrating a changeover switch placed on a circuitboard;

FIG. 26 is a view illustrating a state in which the operation memberdetached from the upper cover is directly placed on the main unitwithout upper cover;

FIG. 27 is a partially cross-sectional view taken along an arrow X inFIG. 1 in a state in which the upper cover is assembled;

FIG. 28 is a perspective view illustrating the note PC in the openedstate from which the upper cover of the main unit is detached;

FIG. 29 is an expanded perspective view illustrating a portion of aswitch board;

FIG. 30 is a view illustrating a back surface of the switch board and aportion of a cable hidden by the switch board after the switch board isunscrewed;

FIG. 31 is a view illustrating the upper surface of the main unit fromwhich the upper cover is detached and a keyboard is further detached;

FIG. 32 is a view illustrating the upper surface of the main unit in astate in which the plate member is further detached from the uppersurface of the main unit illustrated in FIG. 31;

FIG. 33 is a view illustrating the main unit, from which a bottom coverthereof is detached, seen from a bottom side;

FIG. 34 is a view illustrating only the plate member appeared in FIG.31;

FIG. 35 is a perspective view illustrating a back surface of the platemember facing the circuit board;

FIG. 36 is a cross-sectional view taken along an arrow Y-Y in FIG. 1;and

FIG. 37 is a cross-sectional view taken along an arrow Z-Z in FIG. 1.

DESCRIPTION OF EMBODIMENT

An embodiment of the present invention will be described below.

FIG. 1 is a perspective view illustrating an appearance of a notebookpersonal computer (note PC) in an opened state as one embodiment of anelectronic apparatus. FIG. 2 is a perspective view illustrating anappearance of the same note PC as that illustrated in FIG. 1 in a firstclosed state. FIG. 3 is a view illustrating an appearance of the samenote PC as those illustrated in FIGS. 1 and 2 in a second closed state.FIG. 4 is a view illustrating a bottom surface of the same note PC asthose illustrated in FIGS. 1 to 3.

A note PC 10 includes a main unit 20 and a display unit 30 asillustrated in FIG. 1. The display unit 30 is connected to the main unit20 by a hinge 40.

The main unit 20 includes a keyboard 21 and various operation buttons 22such as a power supply button 22 a on its upper surface.

Moreover, the display unit 30 includes a display screen 31, afingerprint sensor 32, and the like.

The hinge 40 is a biaxial hinge having a first rotary shaft and a secondrotary shaft. The first rotary shaft is a horizontal shaft that opensand closes the display unit 30 onto the main unit 20. The second rotaryshaft is a shaft that is perpendicular to the first rotary shaft androtates the display unit 30 in the opened state to the main unit 20.

By using the hinge 40, the note PC 10 includes: the opened stateillustrated in FIG. 1; the first closed state (see FIG. 2) where thedisplay unit 30 is directly closed onto the main unit 20 from the openedstate; and the second closed state (see FIG. 3) where the display unit30 in the opened state illustrated in FIG. 1 is closed onto the mainunit 20 after its direction is inverted.

In the first closed state illustrated in FIG. 2, the display screen 31is directed toward the main unit 20 and a back surface of the displayunit 30 appears on an outer surface of the PC 10. The first closed statecorresponds to a state in which the note PC 10 is not used.Additionally, in the second closed sate illustrated in FIG. 3, thedisplay screen 31 appears on the outer surface of the PC 10. The secondclosed state corresponds to a state in which the note PC 10 can be usedas a so-called slate PC.

Here, a housing of the display unit 30 has a base body 310 (see FIG. 2)and a frame body 320. The base body 310 has a plate section which coversthe back surface of the display screen 31, and a side surface sectionwhich is formed on a peripheral edge of the plate section in a standingmanner, and houses therein electronic components. The frame body 320covers a peripheral edge of the base body 310 having therein an opening321 that exposes the display screen 31 to the front of the PC 10, andforms a front surface of the display unit 30 together with the displayscreen 31. The frame body 320 is screwed into the base body 310 withscrews 33 located at four corners.

The main unit 20 illustrated in FIG. 4 includes, on its bottom surface,a detachable battery unit 23 and an outlet 249 for exhausting air heatedinternally.

It is noted that the appearance of the note PC 10 has been summarized,and each of various members, which may be needed for later descriptionand have not been described yet, is to be described as needed.

(Structure of Radio Communication Antenna)

FIGS. 5 and 6 are external perspective views of the same note PC asthose illustrated in FIGS. 1 to 4, and respectively illustrate a statein which an antenna unit is provided in a standing manner in the openedstate and a state in which the antenna unit is provided in ahorizontally extending manner in the opened state.

The display unit 30 of the note PC 10 has a plate piece-like antennaunit 34. The antenna unit 34 is housed in an antenna housing section 35of the display unit 30 to be rotatable about a screw 33 a on an upperleft end of the display unit 30 illustrated in FIG. 5. The antenna unit34 is pulled out from the antenna housing section 35 and stopped at twopositions, that is, the state in which it is vertically erected asillustrated in FIG. 5 and the state in which it is horizontally extendedas illustrated in FIG. 6. Here, the antenna housing section 35 is formedat a position which includes an upper left corner of the display unit 30of the base body 310 (see FIG. 2) and extends downward along a left sidefrom the upper left corner. The antenna housing section 35 is coveredwith the frame body 320 on its front surface and has an opening 351 forpulling out the housed antenna unit 34 on its left side surface.

Moreover, the antenna unit 34 has, on its top end portion, first andsecond protrusions 341 and 342 each protruding in an extension directionof a corresponding side. Functions of these first and second protrusions341 and 342 will be described later.

FIG. 7 is a front view illustrating a housed state of the antenna unit34.

When being housed in the antenna housing section 35, the antenna unit 34is locked by a locking mechanism 36 so as not to protrude from theantenna housing section 35. When the user slides a slide lever 361, thelocking mechanism 36 is released to allow the antenna unit 34 to bepulled out from the antenna housing section 35.

Further, a cable 353 electrically connected to the antenna unit 34 isprovided in the display unit 30. The cable 353 is wound about the centerof rotation of the antenna unit 34 in a direction of being rewound whenthe antenna unit 34 is rotated in a direction by being pulled out fromthe antenna housing section 35.

Moreover, the display unit 30 includes one more antenna 37 firmlybuilt-in on its right side. The antenna unit 34 on the left side and theantenna 37 on the right side are paired to form a diversity antenna.

FIG. 8 is a perspective view illustrating a top end portion of theantenna unit 34 and the locking mechanism 36 locking the antenna unit 34after detaching the frame body 320 (see FIG. 7), which covers thesurrounding of the display screen 31, of a front surface of the displayunit 30.

As described above, the antenna unit 34 has the first and secondprotrusions 341 and 342 on its top end portion. The first protrusion 341protrudes so as to extend an inner side of the antenna housing section35 in a state where the antenna unit 34 is housed in the antenna housingsection 35. The second protrusion 342 extends along the side surface ofthe opening 351 of the antenna housing section 35 in the state where theantenna unit 34 is housed in the antenna housing section 35. When theantenna unit 34 is housed in the antenna housing section 35, the firstprotrusion 341 is locked by a locking claw 362 a that forms the lockingmechanism 36. Consequently, the antenna unit 34 is locked and held inthe antenna housing section 35. When the user slides the slide lever 361included in the locking mechanism 36, in a direction of an arrow A, thelocking by the locking claw 362 a is released and the antenna unit 34can be pulled out from the antenna housing section 35.

Note that, on the locking mechanism 36, a small-size circuit board 37 isprovided and thus part of the locking mechanism 36 is hidden under thecircuit board 37.

FIG. 9 is a plan view illustrating the portions of the antenna unit 34and the locking mechanism 36 after detaching the circuit board thatcovers the locking mechanism 36. FIG. 10 is a view illustrating thelocking mechanism 36 with the slide lever 361 slid. In FIG. 10, theantenna unit 34 is not illustrated.

The locking mechanism 36 includes the slide lever 361, a locking member362 and a coil spring 363.

The slide lever 361 is provided at a position adjacent to the top endportion of the antenna unit 34 in the state of being housed in theantenna housing section 35 on the side surface of the display unit 30.The slide lever 361 has two leg sections 361 a extending in a fork shapein the housing of the display unit through an opening (not illustrated)on the side surface of the display unit 30.

The locking member 362 is rotatably pivoted by a boss 311 protrudingfrom a plate section, which covers the back surface of the displayscreen 31, of the base body 310 that forms the housing of the displayunit 30. The locking member 362 includes the locking claw 362 a, anoperation receiving arm 362 b and a push-out arm 362 c.

The operation receiving arm 362 b extends toward the slide lever 361 andhas, on its top end portion, a boss 362 d placed between the two legsections 361 a of the slide lever 361. The operation receiving arm 362 brotates the locking member 362 upon reception of the slide operation ofthe slide lever 361.

When the slide lever 361 is slid, the locking member 362 is rotated asillustrated in FIG. 10. By the rotation of the locking member 362, thelocking claw 362 a releases the locking of the first protrusion 341 (seeFIG. 9) of the antenna unit 34. Further, the push-out arm 362 c pushesthe side surface of the inner side of the antenna unit 34 to push outthe antenna unit 34 from the antenna housing section 35 upon releasefrom the locking by the locking claw 362 a. At this time, the cable 353is wound about the center of the rotation of the antenna unit 34 in thedirection described above, and therefore a force is applied in adirection where the antenna unit 34 pushed out by the push-out arm 362 cis further pushed out. This implements an easy pullout of the antennaunit 34 from the antenna housing section 35.

The user can further pull out the antenna unit 34 by hooking his/herclaw in the second protrusion 342 of the antenna unit 34 pushed out fromthe antenna housing section 35.

The coil spring 363 pushes the leg section 361 a of the slide lever 361and urges the locking member 362 in a direction that maintains aposition where the locking claw 362 a locks the first protrusion 341 ofthe antenna unit 34.

FIG. 11 is an exploded view of the antenna unit 34.

The antenna unit 34 is formed of a plate piece-like upper cover 343, anantenna 344 and a lower cover 345. The upper cover 343 has athrough-hole 343 a on its one end side. The antenna 344 and the lowercover 345 have through-holes 344 a and 345 a, respectively, at positionscorresponding to the through-hole 343 a. The antenna unit 34 isassembled in such a manner that the antenna 344 is fitted into the lowercover 345 and the upper cover 343 is attached to the lower cover 345.The upper cover 343 and the lower cover 345 are formed of flexiblematerials such as elastomer, rubber (NBR, silicone rubber, CR), sheet(PET, PC) and the like. Further, any antenna such as a FPC antenna, asubstrate antenna, a plate antenna or the like may be used as theantenna 344.

FIG. 12 is a perspective view illustrating the center portion of arotation of the assembled antenna unit 34 seen from the upper cover 343side.

As illustrated in FIG. 12, the antenna unit 34 has an insertion hole346. A boss 312 (see FIG. 13), which is disposed on the plate section ofthe housing of the display unit 30 in a standing manner, is insertedinto the insertion hole 346. A bearing section 347, which forms an edgeof the insertion hole 346, has four concave sections 347 a that surroundthe insertion hole 346. The boss 312 corresponds to the protrudingsection. The insertion hole 346 is fixed to the antenna 344 so as to beelectrically conducted therewith by a predetermined fixing method suchas soldering, caulking, bonding, screwing and the like.

FIG. 13 is a view illustrating a rotary shaft of the antenna unit 34 ofthe antenna housing section 35.

At an upper left corner, which is one end of the antenna housing section35, of the display unit 30, the boss 312 is disposed in a standingmanner from the base body 310 that forms the housing of the display unit30. A female screw 312 a is formed at the center of the boss 312.Additionally, at the base of the boss 312, four ribs 313 are formed atpositions separated from one another on the base body 310.

FIG. 14 is a view illustrating a plate member 50 to be fitted into theboss 312 illustrated in FIG. 13.

The metal member 50 illustrated in FIG. 14 has two convex sections 51 bat positions, being separated from each other, on an annular section 51having a hole 51 a into which the boss 312 (see FIG. 13) is to beinserted.

FIG. 15 is a view illustrating a state in which the plate member 50illustrated in FIG. 14 is fitted into the boss 312 illustrated in FIG.13.

The plate member 50 is attached to the boss 312 in a direction whereeach convex section 51 b is placed between adjacent ribs 313.Accordingly, when the convex sections 51 b are pressed, the plate member50 is elastically deformed.

The antenna unit 34 is mounted on the boss 312 after the plate member 50is mounted thereon as illustrated in FIG. 15. The boss 312 is insertedinto the insertion hole 346 of the antenna unit 34 in a direction wherethe end surface having the concave sections 347 a of the bearing section347 (see FIG. 12) of the antenna unit 34 comes in contact with the platemember 50. Here, there are prepared three attitudes including: a statein which the antenna unit 34 is housed in the antenna housing section35; a state in which the antenna unit 34 rotates by 90 degrees andextends horizontally as illustrated in FIG. 6; and a state in which theantenna unit 34 further rotates by 90 degrees and extends upwardly asillustrated in FIG. 5. In each of the attitudes, the convex sections 51b of the plate member 50 are fitted into any two of the four concavesections 347 a of the bearing section 347 of the antenna unit 34 to holdthe antenna unit 34 at the corresponding attitude. When a force in therotational direction of the antenna unit 34 is applied to the antennaunit 34 which is in any one of the three attitudes, the plate member 50is deformed as described above and its locking is released, so that theantenna unit 34 rotates.

As described above, the plate member 50 is mounted on the boss 312 andthe antenna unit 34 is further mounted thereon, and the frame body 320(see, for example, FIGS. 1, 3 and 5), which forms the housing of thedisplay unit 30, is still further mounted thereon. Under such a mountedstate, the frame body 320 is screwed by the screw 33 a (see FIG. 5, forexample) by using the female screw 312 a of the boss 312.

If the support of the antenna unit 34 onto the rotary shaft and thefixing of the frame body 320 are separately made, there is a possibilitythat a thickness of the display unit 30 is increased accordingly.However, in this embodiment, the antenna unit 34 and the frame body 320are integrally screwed together, thereby contributing to a reduction inthickness of the display unit 30. Moreover, in this embodiment, clickingis implemented by using the thin plate member 50, and this point alsocontributes to the reduction in thickness of the display unit 30.

(Switch Structure)

FIG. 16 is a perspective view illustrating a side surface of the samenote PC as those having been described so far in the first closed state.FIG. 17 is a perspective view illustrating a rear side of the note PC inthe second closed state. FIG. 18 is a perspective view illustrating aback surface of the note PC in the opened state.

On the side surface illustrated in FIG. 16, a power supply plug 25 forreceiving power supply from an AC adaptor and an operation member 26 areillustrated.

Further, FIG. 17 illustrates a top end portion 27 a of a rod antenna 27(see FIG. 18).

Furthermore, FIG. 18 illustrates the rod antenna 27 in a state where itis pulled out from the main unit 20.

In the note PC 10, the rod antenna 27 is housed in the main unit 20. Therod antenna 27 can be pulled out from the main unit 20 by pinching thetop end portion 27 a and can be folded as illustrated in FIG. 18.

Here, as will be described later, the operation member 26 is used for aswitch operation of a changeover switch, which is provided at the backof the rod antenna 27 with the rod antenna 27 placed therebetween, andis devised to prevent interference with the rod antenna 27.

FIG. 19 is a view illustrating the note PC 10 in the opened state withan upper cover 210 forming the housing of the main unit 20 detachedtherefrom, together with the detached upper cover 210. FIG. 20 is a viewillustrating only the upper cover 210 seen from an angle at which a sidesurface of the upper cover 210 can be seen.

The housing of the main unit 20 is composed of the upper cover 210illustrated in FIG. 19 and the base body forming the bottom portion ofthe main unit 20 (see FIG. 4), the upper cover 210 and the base bodyextending in substantially parallel with each other. The base body andthe upper cover 210 form a side surface for connecting the peripheraledge of an upper surface (upper cover 210) and that of a bottom surface(base body) to each other.

Inside the housing of the main unit 20, the circuit board extends insubstantially parallel with the upper surface and the bottom surface.

The upper cover 210 is a frame-shape cover member having an opening 211through which an upper portion of the keyboard 21 mounted on the mainunit 20 is exposed. The upper cover 210 further includes the variousoperation buttons 22 such as the power supply button 22 a.

Moreover, multiple detection switches 28 for detecting depressions ofthe various operation buttons 22, such as the power supply switch 28 a,are provided at positions right below the operation buttons 22 locatedon the upper cover 210 of the main unit 20. Further, in the main unit20, the rod antenna 27 is housed at a position adjacent to just theinner side of an operation piece 261 (to be described later) of theoperation member 26. FIG. 19 illustrates a state in which part of therod antenna 27 is drawn.

FIG. 21 is a view illustrating an inner side of a portion where theoperation member 26 is placed of the upper cover 210 after putting theupper cover 210 upside down. In FIG. 21, the operation member 26 (seeFIGS. 19 and 20) is also detached.

As illustrated in FIG. 21, the upper cover 210 has on its side surfacean opening 212 through which the operation member 26 passes. Further,the upper cover 210 has two hooks 213 and 214 inside the opening 212.The larger-sized hook 213 of these two hooks 213 and 214 is one forassembling the upper cover 210.

The smaller-sized hook 214 has a function of supporting the operationmember 26 and a function of restricting the range of the slide operationof the operation member 26.

FIG. 22 is a view illustrating only the operation member 26 detachedfrom the upper cover 210. In FIG. 22, illustrated is a perspective viewof the operation member 26 positioned upside down as in FIG. 21. FIG. 23is a view illustrating a state in which the operation member 26 isattached to the upper cover 210 (before operation). FIG. 24 is a viewillustrating a state in which the operation member 26 is attached to theupper cover 210 (after operation).

The operation member 26 illustrated in FIG. 22 has the operation piece261 and an operation arm 262. The operation piece 261 is located outsidethe housing of the main unit 20 and receives a slide operation by theuser. The operation arm 262 inwardly extends from the operation piece261 through the opening 212 illustrated in FIG. 21 and switches thechangeover switch to be described later. Here, the changeover switch(specifically, a changeover lever 291 of a changeover switch 29illustrated in FIG. 25) is arranged in a position that interferes withthe rod antenna 27 when the opening 212 and the changeover switch arelinearly connected to each other. The operation arm 262 has a recess 262a that bypasses the rod antenna 27. Moreover, the operation arm 262 hasan opening 262 b and a changeover section 262 c. The opening 262 b isone through which the hook 214 illustrated in FIG. 21 passes. Thechangeover section 262 c comes in contact with the changeover switch atits top end portion to switch the changeover switch. The changeoversection 262 c has an inclined surface 262 d and a vertical wall surface262 e continuous to the inclined surface 262 d as illustrated in FIGS.23 and 24. The inclined surface 262 d comes in contact with thechangeover switch at the time of assembling the upper cover 210 andguides the operation piece 261 to an initial position (position wherethe operation piece 261 is moved in a direction of an arrow B(hereinafter direction B) as illustrated in FIG. 23) irrespective ofwhere it is located in the slide range. Further, the vertical wallsurface 262 e comes in contact with the changeover switch after theupper cover 210 is assembled and switches the changeover switch uponreception of the slide operation through the operation piece 261. Theoperation member 26 also has a locking base 262 f by which the hook 214(see FIG. 21) is to be locked.

The operation member 26 is arranged in such a manner that the hook 214passes through the opening 262 b (see FIG. 22) and is locked by thelocking base 262 f (see FIG. 22) of the operation member 26 asillustrated in FIGS. 23 and 24. In this state, the changeover switchcomes in contact with the inclined surface 262 d at the time ofassembling the upper cover 210 to move the operation member 26 in thedirection B as illustrated in FIG. 23, so that the changeover switch andthe vertical wall surface 262 e come in contact with each other. Whenthe operation piece 261 is slid in a direction of an arrow C illustratedin FIG. 24 after the upper cover 210 is assembled, the changeover switchis pushed by the vertical wall surface 262 e to switch the changeoverswitch. An amount of slide operations of the operation piece 261 isrestricted by the hook 214 inserted into the opening 262 b.

FIG. 25 is a view illustrating the changeover switch arranged on acircuit board.

A circuit board 280 extends under the keyboard 21. The changeover switch29 is mounted on the end portion of the circuit board 280 on the rodantenna 27 side. The changeover switch 29 has the changeover lever 291.When the changeover lever 291 is slid in a direction of an arrow C, thestate of the changeover switch 29 is changed. A spring, which urges thechangeover lever 291 in a direction opposed to the arrow C, is built inthe inside of the changeover switch 29. When the slide operation of thechangeover lever 291 in the direction of the arrow C is stopped, thechangeover lever 291 is automatically returned to the original initialposition by the spring. The arrow C, which indicates the direction ofthe slide operation of the operation piece 261 illustrated in FIG. 24,corresponds to the arrow C indicated in FIG. 25, and both of the arrowsC indicate the same direction when the upper cover 24 is assembled.

The changeover switch 29 is mounted on a position along one side of therod antenna 27 on the circuit board 280. The rod antenna 27 is placed ina space formed between the circuit board 280 and the side surface of thehousing of the main unit 20. When the inside of the main unit 20 isviewed through the opening 212 (see FIG. 21) of the upper cover 210assembled with the operation member 26 removed, the rod antenna 27 ispresent between the opening 212 and the changeover switch 29. For thisreason, the rod antenna 27 prevents the changeover lever 291 of thechangeover switch 29 from being recognized from outside. The recess 262a of the operation member 26 illustrated in FIG. 22 is used to bypassthe rod antenna 27 placed at the obstructive position.

FIG. 26 is a view illustrating a state in which the operation member 26detached from the upper cover 210 is directly placed on the main unit 20without the upper cover 210. FIG. 27 is a partially cross-sectional viewtaken along an arrow X in FIG. 1 in a state in which the upper cover 210is assembled.

The operation member 26 is structured to operate the changeover switch29 while bypassing the rod antenna 27.

Note that, an example has been described in which the rod antenna 27 isplaced between the operation piece 261 and the changeover switch 29.However, the component, which is present between the operation piece 261and the changeover switch 29, does not have to be the rod antenna 27.Even when, for example, a stylus pen with which a plane surface istraced and other components are provided therebetween, it is possible tooperate the changeover switch provided at the back of the component byusing the operation member 26 having a structure that bypasses and thusavoids the components.

(Grounding Structure Through Cable)

FIG. 28 is a perspective view illustrating the note PC 10 in the openedstate from which the upper cover 210 of the main unit 20 is detached.

A switch board 230 mounting thereon the four switches 28 including apower supply switch 28 a is illustrated on the right side of the hinge40 illustrated in FIG. 28. A cable 240, which connects between theinside of the main unit 20 and that of the display unit 30, is alsoillustrated.

FIG. 29 is an expanded perspective view illustrating a portion of theswitch board 230.

The hinge 40 has a through-hole 401 which allows the cable 240 extendingfrom the inside of the main unit 20 to pass through the through-hole 401to the inside of the display unit 30.

The switch board 230 is screwed into the housing of the main unit 20with two screws 239 with the cable 240 disposed between itself and agrounding member 250 placed on the housing.

FIG. 30 is a view illustrating a back surface of the switch board 230and a portion of the cable 240 hidden by the switch board 230, after theswitch board 230 is unscrewed and detached from the housing of the mainunit 20.

As illustrated in FIG. 29, the grounding member 250 made of a metalpiece is placed in the vicinity of an inlet of the through-hole 401, onthe main unit side, of the hinge 40 on the housing of the main unit, andthe cable 240 passes thereon. As illustrated in FIG. 30, an outersurface of the cable 240 at a portion adjacent to the inlet of thethrough-hole 401, on the main unit side, of the hinge 40 is covered witha conductive foil 241. The switch board 230 is also placed at a positionadjacent to the inlet of the through-hole 401, on the main unit side, ofthe hinge 40. A grounding pattern 231 extends on a portion of the backsurface of the switch board 230 and comes in contact with the conductivefoil 241 of the outer surface of the cable 240. The switch board 230 hasa positioning hole 232 and two attachment holes 233 and 234. Meanwhile,the housing of the main unit 20 has a positioning boss 269 and two screwbosses 267 and 268. The positioning boss 269 is inserted into thepositioning hole 232 and the switch board 230 is screwed as illustratedin FIG. 29 by using the two attachment holes 233 and 234 and femalescrews 267 a and 268 a formed respectively on the two bosses 267 and268.

The conductive foil 241 of the outer surface of the cable 240 extendsover both a contact portion with the grounding member 250 and a contactportion with the conductive pattern 231 of the switch board 230. Byscrewing the switch board 230, the grounding pattern 231 on the backsurface of the switch board 230 is grounded to the grounding member 250through the conductive foil 241 on the outer surface of the cable 240.

In this manner, the switch board 230 is grounded through the outersurface of the cable 240, thereby eliminating extra wirings forgrounding. This contributes to a reduction in size and weight of thenote PC accordingly.

It is noted that the grounding member 250 is herein provided; however,for example, an inner wall surface of the housing of the main unit 20,which is conductively plated, may be used alternatively. Namely, aseparate member from the housing does not have to be used as a memberthat grounds the conductive pattern 231 on the switch board 230 throughthe outer surface of the cable 240.

(Plate Structure Under Keyboard)

FIG. 31 is a view illustrating the upper surface of the main unit 20from which the upper cover 210 (see FIG. 19) is detached and thekeyboard 21 is further detached. Here, a plate member 270, whichsupports the keyboard 21 (for example, see FIG. 19) from the lower side,extends.

FIG. 32 is a view illustrating the upper surface of the main unit 20 ina state in which the plate member 270 is further detached from the uppersurface of the main unit 20 illustrated in FIG. 31.

Under the plate member 270, the circuit board 280 extends and numerouselectronic components are mounted on the circuit board 280 asillustrated in FIG. 32. Among numerous electronic components mounted onthe circuit board 280, attention is focused on a CPU 281 and a chip set282, which are heat-generating electronic components, and four arrayedmemory ICs 283, whose heat radiation is needed to be considered to somedegree though they do not generate heat as much as the CPU 281 and chipset 282. An opening 284, which serves as an air passage and penetratesfront and back surfaces of the circuit board 280, is formed in thecircuit board 280 at a portion adjacent to the four memory ICs 283. Afan 290 provided on the back surface of the circuit board 280 ispartially exposed through the opening 284.

FIG. 33 is a view illustrating the main unit 20, from which a bottomcover thereof is detached, seen from a bottom side.

In FIG. 33, the fan 290 partially exposed in FIG. 32 appears. The fan290 blows air to an air passage 299 The air blown from the fan 290passes through the air passage 299 and is exhausted outside the mainunit 20 from the outlet 249 (see FIG. 4) located at the bottom surfaceof the main unit 20 (see also FIG. 37 to be described later).

FIG. 34 is a view illustrating only the plate member 270 appeared inFIG. 31. FIG. 35 is a perspective view illustrating a back surface ofthe plate member 270 facing the circuit board 280. FIG. 36 isacross-sectional view taken along an arrow Y-Y in FIG. 1, and FIG. 37 isa cross-sectional view taken along an arrow Z-Z in FIG. 1.

The plate member 270 has a function of supporting the keyboard 21 (forexample, see FIG. 19) from the lower side. In addition to this, theplate member 270 has a function as a heat radiation member, a functionof forming a cable passage, and a function as an air internal memberthat guides air on the surface of the circuit board 280 (surface of thecircuit board 280 appearing in FIG. 32) to the opening 284.

These functions will be described below.

The plate member 270 has a concave groove 271, which is recessed from areference surface of the plate member 270, on an upper surface (surfaceindicated in FIGS. 33 and 34) facing the side opposed to the circuitboard 280. The plate member 270 also has a convex line 272, whichcorresponds to the concave groove 271 on the upper surface, on a lowersurface (surface indicated in FIG. 35) facing the circuit board 280. Theconcave groove 271 is used as a passage for a cable 291 as illustratedin FIGS. 31 and 36. The plate member 270 is electrically grounded andtherefore a structure is achieved in which electronic components on thecircuit board 280 and the cable 291 are electrically isolated from eachother by the plate member 270 to prevent noise from being easily mixedmutually.

Further, the convex line 272 formed on the lower surface of the platemember 270 extends along the four memory ICs 283 as illustrated in FIG.37. Here, the convex line 272 comes close to the memory ICs 283 beingthe heat-generating components to serve to absorb heat from the memoryICs 283 into the plate member 270. As illustrated in FIGS. 35 and 36,inclined surfaces 272 a and 272 b are formed on both sides of the convexline 272. These inclined surfaces 272 a and 272 b are useful to allowair on the upper surface of the circuit board 280 to flow into theopening 284 smoothly, thus improving efficiency of heat radiation due tosmooth air flow.

Moreover, the plate member 270 has recesses 273 and 274 when seen fromthe upper surface (the surface illustrated in FIG. 34), that is,protrusions 275 and 276 when seen from the lower surface (the surfaceillustrated in FIG. 35). These protrusions 275 and 276 are provided atpositions corresponding to the CPU 281 and chip set 282 beingheat-generating electronic components on the circuit board 280illustrated in FIG. 32. These protrusions 275 and 276 come in closecontact with the CPU 281 and chip set 282 with heat transmission pads275 a and 276 a formed therebetween, respectively, and serve to transmitheat to the plate member 270 from the CPU 281 and chip set 282.

Heat generated by the heat-generating electronic components such as theCPU 281, chip set 282, four memory ICs 283 and the like is directlytransmitted to air therearound. Or, the heat is transmitted to the platemember 270, and the heat is dispersed by the plate member 270 andtransmitted to air from the plate member 270. The air thus heated isabsorbed by the fan 290 through the opening 284 while being guided bythe inclined surfaces 272 a and 272 b of the convex line 272 of theplate member 271, and is exhausted outside the main unit 20 from theoutlet 249 by the fan 290.

In the electronic apparatus disclosed in the present embodiment, theopening is formed in the circuit board and the guiding inclined surfaceis formed on the plate member extending while facing the circuit board.Accordingly, air on the first surface, on which the heat-generatingelectronic component is mounted, of the circuit board is guided to theopening by the guiding inclined surface and flows into the secondsurface side. Therefore, the air flows smoothly, contributing toimproved efficiency of heat radiation.

According to the electronic apparatus disclosed in the presentembodiment, smooth air flow along a circuit board is realized and heatis efficiently radiated.

All examples and conditional language recited herein are intended forpedagogical purposes to aid the reader in understanding the inventionand the concepts contributed by the inventor to furthering the art, andare to be construed as being without limitation to such specificallyrecited examples and conditions, nor does the organization of suchexamples in the specification relate to a showing of the superiority andinferiority of the invention. Although the embodiments of the presentinventions have been described in detail, it should be understood thatthe various changes, substitutions, and alterations could be made heretowithout departing from the spirit and scope of the invention.

1. An electronic apparatus comprising: a housing that includes twosurfaces extending in parallel with each other, and a side surfaceconnecting peripheral edges of the two surfaces to each other; a circuitboard that is placed in the housing and extends in parallel with the twosurfaces; a plate member that extends to face a first surface of thecircuit board; and a fan that is provided on a second surface of thecircuit board, wherein the circuit board has a heat-generatingelectronic component mounted on the first surface and an opening throughwhich air on the first surface flows to the second surface, and theplate member includes: a concave groove formed in a first surface facinga side opposed to the circuit board; a convex line formed on a secondsurface facing the circuit board on a portion corresponding to a backsurface of the concave groove; and a guiding inclined surface formed onthe back of the convex line to guide air on the first surface of thecircuit board to the opening.
 2. The electronic apparatus according toclaim 1, wherein the convex line extends while facing a plurality ofheat-generating electronic components mounted on the first surface ofthe circuit board.
 3. The electronic apparatus according to claim 1,wherein the plate member further includes a heat receiving section whichis formed in a convex shape to the heat-generating electronic componentmounted on the circuit board, and comes in contact with theheat-generating electronic component through a heat-transfer agent forclose contact.
 4. The electronic apparatus according to claim 1, furthercomprising a cable that extends through the concave groove.
 5. Theelectronic apparatus according to claim 1, further comprising a keyboardthat is placed in contact with the first surface of the plate member. 6.The electronic apparatus according to claim 5, further comprising asecond housing that has a display panel and is openably and closablyconnected to the housing.